Boeing is undertaking significant design changes to the door plug of its 737 MAX 9 aircraft to prevent future blowouts, following a mid-air incident on an Alaska Airlines flight in January. The company's senior vice president, Elizabeth Lund, announced these changes during a two-day National Transportation Safety Board (NTSB) hearing. The incident exposed severe communication issues among the crew and highlighted broader safety and quality management problems within Boeing. The NTSB's investigation revealed that the door plug was missing essential bolts, a result of rushed and pressured work environments at Boeing and its supplier, Spirit AeroSystems. Workers testified about inadequate training and the stress of fast-paced production demands. NTSB Chair Jennifer Homendy criticized Boeing's safety culture, stating the company has a long way to go in addressing these issues.